QUANTITATIVE EFFECTS OF TYPICAL AND ATYPICAL NEUROLEPTICS ON SMOOTH-PURSUIT EYE TRACKING IN SCHIZOPHRENIA

Smooth pursuit eye movement (SPEM) gain, total saccades, and subtypes of saccades were quantified from the visual pursuit tracking of 26 flu phenazine-treated patients with schizophrenia and 42 normal controls. Tracking was repeated in 16 patients who underwent a placebo-controlle d, double-blind crossover comparison of fluphenazine and clozapine. Fl uphenazine-treated patients showed significant reduction in SPEM gain and significant increases in both total, intrusive, and anticipatory s accades and in saccadic amplitude, when compared to controls. Clozapin e significantly reduced SPEM gain and significantly increased total an d catch-up saccades, when compared to placebo or fluphenazine. High am plitude of intrusive saccades in drug-free patients predicted poor res ponse to clozapine, suggesting that intact frontal cortical function m ay enable optimal clozapine response.